1. Technical Field
The present disclosure relates to automated booklet makers, in which sheets forming a booklet are folded upon action of crease rollers.
2. Brief Discussion of Related Art
Booklet makers are well-known devices for forming folded booklets which are stapled or otherwise joined along the crease thereof. It is becoming common to include booklet makers in conjunction with office-range printers. The word “printer” as used herein encompasses any apparatus, such as a copier, digital copier, bookmaking machine, facsimile machine, multifunction machine, etc. which performs a print outputting function for any purpose. In basic form, a booklet maker includes a slot for accumulating processed sheets, as would be produced by a printer. The accumulated sheets, forming the pages of a booklet, are positioned within the stack so that a stapler mechanism and complementary anvil can staple the stack precisely along the intended crease line. The creased and stapled sheet sets are then pushed, by a crease blade, completely through crease rollers to form the final main fold in the finished booklet. The finished booklets are then accumulated in a tray downstream of the crease rollers.
In order to form a tight crease, after the booklet is initially folded by a first set of crease rollers, the entire booklet may be passed through a second set of crease rollers. The second set of crease rollers are typically held together under significant tension by a biasing device so that a tight, high quality finish crease is formed along the edge or spine of the booklet. This roller pressure, which acts over the entire booklet, has a tendency to cause image transfers between the pages. The quality of the images is therefore compromised.
Accordingly it would be desirable to provide a booklet maker having a high quality tight crease along the spine without distorting the images.